The proposed project will continue to elucidate the physiological role of cartilage lysozyme in cartilage metabolism. Originally, we were able to show that cartilage lysozyme can disaggregate proteoglycan aggregates either from bovine nasal septa or present in the aspirated cartilage fluid of rat growth plates. Even though lysozyme does not act as a hyaluronidase, a specific interaction between lysozyme and cartilage hyaluronic acid has been shown and will be investigated in more detail. This interaction cannot be called an anion-cation salt-like interaction since it resides dissociation in dissociative solvents such as 4 M guanidinium hydrochloride. An oligosaccharide derived from hyaluronic acid has been isolated from hyaluronic acid which seems to be responsible for this specific interaction. Using biochemical as well as immunological methods, it is intended to purify and identify this oligosaccharide from hyaluronidase digestion. Tissue culture experiments are also planned to study the correlation between the biosynthesis of lysozyme and hyaluronic acid. Endogenous cartilage lysozyme seems to be able to "induce" calcification in aspirates of the late columnar and early hypertrophic zones of growth plates, thus indicating that cartilage lysozyme may act as a regulator of calcification, by rearrangement of proteoglycan aggregates, a hypothesis which will be evaluated in the proposed study.